At present, the third-generation mobile communication system introduces a 2×2 MIMO (Multiple-input Multiple-output, multiple-input multiple-output) technology to increase a downlink data transmission rate. Specifically, after a primary transport block and a secondary transport block (if any) undergo transmission channel processing (namely, code modulation), the two blocks undergo spread spectrum and are scrambled. Then a primary data stream and a secondary data stream each are weighted by using a weight and the two data streams are sent to two antennas, respectively, and are combined with other data for transmission. A scheduling policy used by a base station such as a transport block size and used weight information depends on channel quality indication information (CQI, Channel Quality Indication) and precoding indication information (PCI, Precoding Control Indication) fed back by a user equipment. In the 2×2 MIMO technology, one piece of feedback information of a user equipment includes a maximum of two CQI values, and can indicate that channel rank information (RI, Rank Indication) is maximally 2.
During the implementation of transmission of user equipment feedback information, the inventor finds that the prior art has at least the following problem: At present, in the 4-antenna technology introduced by the third-generation mobile communication system to further increase the downlink data transmission rate, the channel RI value is maximally 4, but in the conventional 2×2 MIMO technology, feedback information can only indicate that the RI value is maximally 2.